In a medium bowl add the chicken, Greek yogurt, turmeric, salt, and mix well. Set aside and let it marinate. About 20 minutes
Add ginger, garlic, and onion in a food processor and grind them into a paste.
Heat oil over medium flame in a heavy bottom pan.
Add the onion mixture to the pan and fry till golden brown. This will take anywhere from 15-20 minutes. Do not try to rush this process becauase this is what will give flavor to the curry. Stir the mixture frequently, it shouldn’t stick to the bottom of the pan. If it does add a tablespoon of water to help it release.
Add the chopped chilies and fry for 20 seconds.
Add chopped tomatoes, coriander powder, fennel powder, cumin powder, and chili powder to the pan.
Fry the spice paste (masala) on medium to medium low flame for 8-10 minutes. Again if the masala starts to stick just add a bit of water.
Just like frying the onions you do not want to rush the process of properly cooking the masala paste because this will help to flavor the curry.
The masala paste is cooked properly once it begins to release oil from the sides
Turn up the heat to medium high, add the chicken, mix thoroughly to incorporate the spice paste. Fry for about 5 minutes till the chicken pieces are sealed.
Add water, scrape the bottom to release any spice paste and give the curry a good stir.
Season to taste and simmer the curry over low heat with a lid for 25 minutes or till the chicken is full cooked.
Stir the curry halfway through. If the gravy is too thick just add a little more water.
Take the lid off and stir in the garam masala.
Garnish with fresh coriander and enjoy.
*Notes: If you prefer more gravy just add more water. I prefer a thicker gravy when eating with a naan.
Be careful not to add too much water though, the rule of thumb is usually to add enough water to cover the chicken pieces. The chicken as it cooks will also release its own water.